CN113169949B - Symbol constellation diagram for data transmission - Google Patents
Symbol constellation diagram for data transmission Download PDFInfo
- Publication number
- CN113169949B CN113169949B CN201980082072.6A CN201980082072A CN113169949B CN 113169949 B CN113169949 B CN 113169949B CN 201980082072 A CN201980082072 A CN 201980082072A CN 113169949 B CN113169949 B CN 113169949B
- Authority
- CN
- China
- Prior art keywords
- constellation
- equal
- symbol
- dimensional
- symbol constellation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
- H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
- H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
- H04L27/3405—Modifications of the signal space to increase the efficiency of transmission, e.g. reduction of the bit error rate, bandwidth, or average power
- H04L27/3411—Modifications of the signal space to increase the efficiency of transmission, e.g. reduction of the bit error rate, bandwidth, or average power reducing the peak to average power ratio or the mean power of the constellation; Arrangements for increasing the shape gain of a signal set
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
The present invention relates to data transmission processes, and more particularly to modulation methods using a two-dimensional symbol constellation. To this end, the invention proposes a transmitting device and a receiving deviceBoth are configured to be suitable for use with two-dimensional symbol constellations. The transmitting device is used for obtaining a message to be transmitted; mapping the obtained message to two-dimensional 2 n On the symbol constellation, to obtain a sequence of discrete constellation symbols, where n is an odd number not less than 3. Correspondingly, the receiving device is configured to receive a noisy discrete constellation symbol sequence; using two dimensions 2 n The symbol constellation demaps the noisy discrete constellation symbol sequence into output data, where n is an odd number not less than 3. Thus, a two-dimensional symbol constellation is proposed, which consists of points arranged along the perimeter of q concentric squares.
Description
Technical Field
The present invention relates to data transmission processes, and more particularly to modulation methods using a two-dimensional symbol constellation. The present invention provides a transmitting device and a receiving device, both using a two-dimensional symbol constellation.
Background
In digital communications, transmitted messages are mapped onto discrete alphabets, commonly referred to as symbol constellations.
In the case of a bandpass system, two quadrature carrier phases (commonly denoted as an in-phase (I) component and a quadrature (Q) component) are used to span the symbol space. Thus, a two-dimensional symbol constellation is a natural choice. In contrast, one-dimensional constellations are typically employed on low-pass systems. However, if two different signaling intervals are used across a two-dimensional space, the low-pass system may also employ a two-dimensional constellation.
The size of the symbol constellation determines how many bits can be mapped on each symbol. With 2 of n A constellation of symbols may carry n bits for each signaling interval.
The bijection between the symbols and the binary n-tuples is called bit mapping. In Gray (Gray) mapping, the binary n-tuples of any adjacent two symbols differ by only one bit. Not all symbol constellations allow gray mapping. If there is no Gray mapping, the mapping that minimizes the Hamming (Hamming) distance between binary n-tuples of adjacent symbols is called quasi-Gray (quasi-Gray) mapping.
A practical channel coding method, known as bit-interleaved coded modulation (bit-interleaved coded modulation, BICM), consists in concatenating a binary encoder and a bit mapper at the transmitter and a bit demapper and a binary decoder at the receiver. In case BICM is used, (quasi) gray mapping achieves the best performance. At the receiver, the bit demapper may provide tentative decisions (hard demapper) or probabilities of 0 or 1 for each bit (soft demapper).
The transmitter converts the sequence of discrete constellation symbols into a signal (e.g., a bandpass signal) that matches the transmission channel. Most transmitters in practice are limited in terms of the output power of the output signal. Such limitations may be caused by different factors, such as thermal problems or nonlinear distortion.
If the available power budget depends on the band-pass power amplifier, the power constraint applies to the two-dimensional constellation (i.e., applies jointly to the I and Q components). However, in many systems including optical systems, the power limitations apply solely to the I and Q components of the constellation.
However, known constellations are optimized for noise sensitivity while ignoring peak-to-average power ratio (PAPR), or are optimized for PAPR in two dimensions. Up to now, one-dimensional peak-to-average power ratio (PAPR in one dimension, PAPR-1D) has not been considered.
Disclosure of Invention
In view of the above limitations and disadvantages, alternative symbol constellations are desirable. The aim is to provide a symbol constellation that is optimized for peak signal power in one dimension.
This object is achieved by the embodiments provided in the appended independent claims. Advantageous implementations of embodiments of the invention are further defined in the dependent claims.
A first aspect of the invention provides a transmitting device adapted to use a two-dimensional symbol constellation, the transmitting device being arranged to:
obtaining a message to be sent; mapping the obtained message to two-dimensional 2 n On the symbol constellation, to obtain a sequence of discrete constellation symbols, wherein n is an odd number not less than 3; wherein, two-dimension 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A plurality of points, wherein q is a positive integer; and transmitting the symbol.
With the symbol constellation used by the device of the first aspect, an optimization for peak signal power in one dimension is achieved. This is because the points of the constellation are arranged on a square instead of a circle.
Introduces a two-dimensional symbol constellation diagram which consists of points distributed along the circumferences of q concentric squares
I.e. q is a positive integer). Although this configuration can be used for any 2 n Symbol constellation (n is an integer), but this configuration is particularly useful for odd numbers of n, since in case n is an odd number, the alternative solution is not satisfactory for the type of transmitter considered.
In an embodiment of the first aspect, the transmitting device is further configured to: converting the sequence of discrete constellation symbols into a signal that matches the transmission channel; and to transmit signals, in particular to a receiving device.
In particular, the transmitter may convert the sequence of discrete constellation symbols into a signal that matches the transmission channel, e.g., into a bandpass signal.
In an embodiment of the first aspect, two-dimensional 2 n The points of each concentric square of the symbol constellation are evenly distributed along the circumference and the four points are located at the corners.
In contrast to many known geometric constellations (which exhibit a circular or quasi-circular shape), two-dimensional 2 according to the present invention n The constellation (due to its square shape) is advantageous for a particular transmitter whose power budget is limited in each dimension alone rather than in two dimensions.
In an embodiment of the first aspect, two-dimensional 2 n The symbol constellation is also defined by the following features: the sides of the concentric squares are parallel to the I and Q axes, the centers of the squares coincide with the origin of the I-Q plane, and the length of the side of the ith square is L i ，L 1 <L 2 <…<L q The ith square contains 4.N i Points, N i Is an integer and N 1 ≤N 2 ≤…≤N q 。
In particular, by L i And N i (i=1, 2, …, q) vs. two-dimensional 2 n The symbol constellation is parameterized.
In an embodiment of the first aspect, the cost function has been minimized for two-dimensional 2 n Parameter l= [ L ] of symbol constellation 1 ,…,L q ]And n= [ N ] 1 ,…,N q ]Optimization was performed.
Parameters may be optimized by minimizing a required signal-to-noise ratio (RSNR) at a target Bit Error Rate (BER) and PAPR-1D.
In an embodiment of the first aspect, the cost function is expressed as:
f(L,N)＝RSNR+PAPR1D，
wherein l=[L 1 ,L 2 ,...,L q ]，N＝[N 1 ,N 2 ,...,N q ]RSNR denotes RSNR at a target BER, PAPR1D denotes PAPR in one dimension, and RSNR and PAPR1D are expressed in decibels (dB).
The function essentially describes the ratio of peak signal power to average noise power for one dimension. The selection is based on the following observations: the basic transmitter resource is one-dimensional peak signal power, rather than average signal power or two-dimensional peak signal power. The optimization of the cost function means that the constellation achieves good performance in one dimension in terms of BER versus peak power to noise ratio.
In an embodiment of the first aspect, n is equal to 5, q is equal to 3, L 1 Equal to 2, L 2 Equal to 6, L 3 Equal to 10, and N 1 Equal to 1, N 2 Equal to 3, N 3 Equal to 4.
In a specific embodiment, an optimized 32-symbol constellation is presented.
In an embodiment of the first aspect, n is equal to 7,q equal to 6, L 1 Equal to 2, L 2 Equal to 6, L 3 Equal to 10, L 4 Equal to 14, L 5 Equal to 18, L 6 Equal to 22, and N 1 Equal to 1, N 2 Equal to 3, N 3 Equal to 5,N 4 Equal to 7, N 5 Equal to 7, N 6 Equal to 9.
In another specific embodiment, an optimized 128 symbol constellation is presented.
In an embodiment of the first aspect, the transmitting device is configured to: performing Gray mapping or quasi-Gray mapping to map the obtained message to two-dimensional 2 n On the symbol constellation.
Gray mapping or quasi-Gray mapping may be implemented to achieve optimal performance.
A second aspect of the invention provides a receiving device adapted to use a two-dimensional symbol constellation, the receiving device being arranged to: receiving a noise discrete constellation symbol sequence; using two dimensions 2 n The symbol constellation demaps the noisy discrete constellation symbol sequence into output data, whereinn is an odd number not less than 3, wherein two dimensions 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A dot composition, wherein q is a positive integer.
The device of the second aspect supports the advantages of the device of the first aspect described above.
In an embodiment of the second aspect, the receiving device is adapted to receive a signal, in particular a signal from the transmitting device; and converting the received signal into a noisy discrete constellation symbol sequence.
At the receiving device, the signal sent from the transmitting device may be received and converted. The sequence obtained after the transmission and conversion process may not be the ideal sequence of discrete constellation symbols, but a noisy sequence of discrete constellation symbols.
In an embodiment of the second aspect, the receiving device is configured to perform hard or soft demapping based on gray mapping or quasi-gray mapping.
At the receiver side, the bit demapper may provide tentative decisions (hard demapper) or probabilities of 0 or 1 for each bit (soft demapper).
A third aspect of the invention provides a method of transmitting a message using a two-dimensional symbol constellation, the method comprising: obtaining a message to be sent; mapping the obtained message to two-dimensional 2 n On the symbol constellation, n is an odd number not less than 3, wherein, two-dimensional 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A plurality of points, wherein q is a positive integer; and transmitting the symbol.
The method of the third aspect may have embodiments corresponding to embodiments of the apparatus of the first aspect. The method of the third aspect and embodiments thereof provide the same advantages and effects as the transmitting device of the first aspect and corresponding embodiments thereof described above.
A fourth aspect of the invention provides a method of receiving a message using a two-dimensional symbol constellation, the method comprising: receiving a noise discrete constellation symbol sequence; using two dimensions 2 n Symbol constellation demapping a noisy discrete constellation symbol sequenceFor outputting data, where n is an odd number not less than 3, where two-dimensional 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A dot composition, wherein q is a positive integer.
The method of the fourth aspect may have embodiments corresponding to those of the apparatus of the second aspect. The method of the fourth aspect and its embodiments provide the same advantages and effects as the receiving device of the second aspect and its corresponding embodiments described above.
It should be noted that all devices, elements, units and means described in this application may be implemented in software or hardware elements or any combination thereof. All steps performed by each entity described in this application, as well as functions described as performed by each entity, are intended to mean that the corresponding entity is adapted to, or used to perform, the corresponding steps and functions. In the following description of specific embodiments, it should be apparent to those skilled in the art that the methods and functions may be implemented in corresponding software or hardware elements or any combination thereof, even if a specific function or step performed by an external entity is not reflected in the description of a specific detailed element of an entity performing the specific step or function.
Drawings
The above aspects and embodiments of the present invention will be explained in the following description of specific examples with respect to the accompanying drawings, in which:
fig. 1 shows an example of a coherent optical transmitter.
Fig. 2 shows an example of a cross 32QAM (left) and a cross 128QAM (right) symbol constellation.
Fig. 3 shows a transmitting device according to an embodiment of the invention.
Fig. 4 shows an example of a mapping employed in a 32-point constellation and octal notation according to an embodiment of the present invention.
Fig. 5 shows an example of the performance of a 32 symbol constellation on an AWGN channel according to an embodiment of the present invention.
Fig. 6 shows an example of a mapping employed in a 128-point constellation and octal notation in accordance with an embodiment of the present invention.
Fig. 7 shows an example of the performance of a 128 symbol constellation on an AWGN channel in accordance with an embodiment of the present invention.
Fig. 8 shows a receiving apparatus according to an embodiment of the present invention.
Fig. 9 shows a schematic flow diagram of a method of transmitting a message using a two-dimensional symbol constellation in accordance with an embodiment of the present invention.
Fig. 10 shows a schematic flow diagram of another method of receiving a message using a two-dimensional symbol constellation in accordance with an embodiment of the present invention.
Detailed Description
As shown in fig. 1, in a coherent optical transmitter, the power of the transmitted laser light is divided equally between two orthogonal polarization planes X and Y, and each polarization plane is divided equally between an I component and a Q component. Each branch (XI, XQ, YI, YQ) is modulated via a Mach-Zehnder modulator that "sculptures" the desired signal shape by attenuating the laser light. Thus, the maximum power per dimension is limited. Furthermore, in this type of emitter, the laser continues to emit maximum power and modulation is achieved by dissipating the excess power. Thus, the cost in terms of power efficiency and heat dissipation is determined by the peak power rather than the average power.
In general, the available transmit power is directly related to the maximum link budget. In some applications, the power of the two-dimensional signal may be enhanced along the link by using an inline repeater (i.e., an amplifier). However, this requires additional components and can deteriorate the signal-to-noise ratio of the signal.
In any case, for a given transmitter with a given peak power, the choice of symbol constellation will affect the average transmit power. It is therefore desirable to be able to determine symbol constellations that maximize the average transmit power without compromising the sensitivity of the system to noise.
Finding a two-dimensional constellation that achieves this goal is a problem to be solved for the case where the power budget of the transmitter is limited individually in each dimension.
Two-dimensional constellation for quadrature amplitudeIn a modulation (QAM) scheme. Many QAM constellations have been proposed. For n=2·m, there is 2 m ×2 m Square constellations of individual points (e.g., 16QAM, 64QAM, 256 QAM) are a common choice. For n=2·m+1, cross constellations (e.g., cross 32QAM and cross 128 QAM) are the most common choices. Fig. 2 shows an example of cross 32QAM and cross 128QAM symbol constellations. The cross constellation does not use corner points and therefore has a reduced peak-to-average power ratio (PAPR) in two dimensions.
In another example, second generation satellite digital video broadcast (digital video broadcasting-satellite 2 nd generation, DVB-S2) systems use a constellation with points distributed along concentric rings. Such a constellation has a lower PAPR in two dimensions than a cross constellation.
However, known 2 including the above-described example n The symbol constellation (where n=2·m) is optimized for noise sensitivity while ignoring the PAPR, or is optimized for the PAPR in two dimensions. Up to now, one-dimensional peak-to-average power ratio (PAPR-1D) is not considered.
Thus, the invention introduces a class of two-dimensional 2 n Symbol constellations (where n is an odd number), such constellations consisting of 2 arranged along the circumference of q concentric squares n Individual point composition [ ]
That is, q is a positive integer).
Fig. 3 shows a transmitting device 300 according to an embodiment of the invention. The transmitting device 300 is configured to obtain a message 301 to be transmitted; mapping the obtained message 301 to two-dimensional 2 n On the symbol constellation 302 to obtain a sequence of discrete constellation symbols 303, where n is an odd number not less than 3, two-dimensional 2 n The symbol constellation 302 consists of 2 arranged along the perimeter of q concentric squares n A plurality of points, wherein q is a positive integer; the symbol 303 is transmitted.
The transmitting device 300 may be a transmitter in an optical system or another communication system and may include components such as a bit encoder and a bit mapper.
The transmitting device 300 may also be used to convert a sequence of discrete constellation symbols into a signal (e.g., a bandpass signal) that matches the transmission channel. In addition, the transmitting device 300 may send a signal to the receiving device 310. The receiving device 310 may be a receiver in an optical system or another communication system and may include components such as a bit decoder and a bit demapper.
The constellation diagram applied in the embodiment of the present invention may satisfy the following conditions: in each concentric square, the dots are evenly distributed along the circumference, and four dots are located at the corners.
Alternatively, the constellation can also be defined by the following features:
the sides of the square are parallel to the I-axis, Q-axis, and the center of the square coincides with the origin of the I-Q plane.
Length of side of ith square L i ，L 1 <L 2 <…<L q 。
The ith square contains 4.N i Points, N 1 ≥N 2 ≥…≥N q 。
Thus, L can be used i And N i (i=1, 2, …, q) parameterizes the constellation. The parameters may be optimized by minimizing the required signal-to-noise ratio (RSNR) at the target Bit Error Rate (BER) and PAPR-1D. In particular, the cost function can be minimized
f(L,N)＝RSNR+PAPR1D(dB), (1)
Wherein L= [ L ] 1 ,L 2 ，…,L q ]And n= [ N ] 1 ,N 2 ，…,N q ]
The function essentially describes the ratio of peak signal power to average noise power for one dimension. The selection was derived from the following observations: the basic transmitter resource is one-dimensional peak signal power, rather than average signal power or two-dimensional peak signal power.
In contrast to many known geometric constellations (which exhibit a circular or quasi-circular shape), the constellation according to embodiments of the present invention (due to its square shape) is specifically designed for a transmitter whose power budget is limited in each dimension individually rather than in two dimensions.
The optimization of the cost function (1) means that the constellation achieves good performance in terms of BER versus peak power to noise ratio. Furthermore, the proposed construction has some characteristics that are attractive in practice.
And pair 2 n The structure of the rules is mandatory, unlike unconstrained optimization, where the positions of the individual symbols are freely optimized. Furthermore, the fact that the symbols are distributed along concentric squares simplifies the implementation of the demapper at the receiving end.
In a typical use case, the selection of the constellation occurs at the design stage. Alternatively, it is also possible to dynamically select the constellation during operation. In this case, a signaling protocol between the transmitting device 300 and the receiving device (e.g., as shown in fig. 8) may be defined.
The constellation is designed to work well with a forward carrier-phase estimation (CPE) scheme that is typically used in high rate applications (e.g., optical communications). Since there are symbol points at each square corner, the constellation is well suited for blind carrier phase estimation, which can be achieved by means of the well-known Viterbi-Viterbi (four times) algorithm (a.j.viterbi and a.n.viterbi's nonlinear estimation of PSK modulated carrier phase and its application in burst digital transmission (Nonlinear estimation of PSK-modulated carrier phase with application to burst digital transmission), "IEEE information theory journal, volume 29, 4, pages 543-551, 1983). In particular, the outer corner symbols provide a very important contribution to the phase estimation, since they exhibit an optimal ratio between symbol energy and noise power.
It should be noted that the construction of the constellation according to embodiments of the present invention may be used for any integer n, but is particularly useful for odd numbers of n, since in case n is odd, alternative solutions are not satisfactory for the type of transmitter considered.
According to an embodiment of the present invention, a 32 symbol constellation is proposed. The parameters of the constellation can be optimized using a cost function (1). The parameters of the optimized 32 symbol constellation are listed in table 2.
Table 2: parameters of optimized 32 symbol constellation
The proposed 32 symbol constellation, i.e. concentric square 32QAM (concentric square-32QAM, cs-32 QAM), is shown in fig. 4, together with the quasi-gray mapping employed.
As shown in fig. 5, a 32 symbol constellation (CS-32 QAM) according to an embodiment of the present invention is shown at E on an additive white gaussian noise (additive white Gaussian noise, AWGN) channel b /N 0 The +PAPR-1D aspect performs approximately 0.5dB better than cross 32QAM (shown on the left side of FIG. 2), where E b Is the average energy per bit, N 0 Is the standard deviation of two-dimensional noise, correspondingly E b /N 0 Is the signal-to-noise ratio employed.
According to another embodiment of the present invention, a 128 symbol constellation is presented. Similar to the 32 symbol constellation according to the previous embodiment, the parameters of the 128 symbol constellation can also be optimized using the cost function (1). The parameters of the optimized 128 symbol constellation are listed in table 1.
Table 1: parameters of optimized 128 symbol constellation
The proposed 128 symbol constellation (i.e., CS-128 QAM) and the quasi-gray mapping employed are shown in fig. 6.
As shown in fig. 7, on an AWGN channel, a 128-point constellation (CS-128 QAM) according to an embodiment of the present invention is shown at E b /N 0 The +PAPR-1D aspect performs approximately 0.3dB better than cross 128QAM (shown on the right side of FIG. 2).
Fig. 8 shows a receiving device 310 according to an embodiment of the invention. The receiving device 310 is arranged to use a two-dimensional symbol constellation. In particular, the receiving device 310 of fig. 8 may be the receiving device 310 of fig. 3. The transmitting device 300 shown in fig. 8 may be the transmitting device shown in fig. 3. The receiving device 310 may be a receiver or may be included in a receiver.
The receiving device 310 may be used to operate in reverse with the transmitting device 300 of fig. 3. In particular, the receiving device 310 is configured to: receiving a sequence of noisy discrete constellation symbols 304; using two dimensions 2 n The symbol constellation 302 demaps a sequence of noisy discrete constellation symbols 304 into output data 305, where n is an odd number not less than 3, where two-dimensional 2 n The symbol constellation 302 consists of 2 arranged along the perimeter of q concentric squares n A dot composition, wherein q is a positive integer.
The receiving device 310 may be a receiver in an optical system or other communication system, including components such as a bit decoder and a bit demapper.
Alternatively, the receiving device 310 may be used to receive signals, in particular signals from the transmitting device 300; and converting the received signal into a sequence of noisy discrete constellation symbols 304. The transmitting device 300 may be a transmitter in an optical system or other communication system, including components such as a bit encoder and a bit mapper.
At the receiving device 310, the signal sent from the transmitting device 300 may be received and converted. The sequence obtained after the transmission and conversion process is not an ideal sequence of discrete constellation symbols, but a sequence of noisy discrete constellation symbols 304.
Alternatively, the receiving device may be further configured to perform hard or soft demapping based on gray mapping or quasi-gray mapping.
At the receiver side, the bit demapper may provide tentative decisions (hard demapper) or probabilities of 0 or 1 for each bit (soft demapper).
The receiving device 310 uses the same constellation 302 as the transmitting device 300. Two-dimensional 2 applied in the present embodiment n The symbol constellation 302 includes information associated with the transmitting device 300All of the features described in the previous embodiments. As explained in the previous embodiments, the constellation is typically fixed and agreed upon prior to operation. If dynamic constellation selection is required during operation, a signaling protocol between the transmitting device 300 and the receiving device 310 needs to be predefined.
Fig. 9 illustrates a method 900 of transmitting a message using a two-dimensional symbol constellation in accordance with an embodiment of the present invention. In particular, method 900 is performed by a transmitting device. The method comprises the following steps: step 901, obtaining a message to be sent; step 902, map the obtained message to two-dimensional 2 n On the symbol constellation, n is an odd number not less than 3, wherein, two-dimensional 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A plurality of points, wherein q is a positive integer; and step 903, transmitting the symbol.
Fig. 10 illustrates a method 1000 of receiving a message using a two-dimensional symbol constellation in accordance with an embodiment of the present invention. In particular, method 1000 is performed by a receiving device. The method comprises the following steps: step 1001, receiving a noisy discrete constellation symbol sequence; step 1002, using two-dimensional 2 n The symbol constellation demaps the noisy discrete constellation symbol sequence into output data, where n is an odd number not less than 3, where two-dimensional 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A dot composition, wherein q is a positive integer.
In summary, the embodiments of the present invention achieve a number of beneficial effects. A class of constellations is presented that is particularly suitable for optical coherent transmission systems and intensity modulated and direct detection (intensity modulation and direct detection, IM-DD) transmission systems. The following advantages are summarized:
the constellation according to an embodiment of the present invention shows a noise sensitivity comparable to a conventional cross constellation and at the same time a higher transmit power is achieved due to reduced PAPR-1D.
In non-amplifying systems, it is particularly important to increase the transmit power to increase the available power budget.
In the case of an amplification system, it is advantageous to increase the transmit power, since it is possible to reduce the error vector magnitude (error vector magnitude, EVM) of the transmitted signal.
The constellation according to an embodiment of the invention can also be employed in IM-DD systems by transmitting the I-component and the Q-component on the following two signaling intervals.
The constellation according to an embodiment of the present invention is also designed to fit well with a forward CPE scheme, which is typically used in optical coherent communication.
The invention has been described in connection with various illustrative embodiments and implementations. However, other variations to and implementation of the claimed invention can be understood and effected by those skilled in the art and practicing the claimed invention, from a study of the drawings, the disclosure, and the independent claims. In the claims and in the description, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single element or other unit may fulfill the functions of several entities or items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
Claims (14)
1. A transmitting device (300) adapted to use a two-dimensional symbol constellation, the transmitting device (300) comprising a transmitting module for:
obtaining a message to be sent (301);
mapping the obtained message (301) to two-dimensional 2 n On the symbol constellation (302) to obtain a sequence of discrete constellation symbols (303), wherein n is an odd number not less than 3;
wherein the two dimensions 2 n The symbol constellation (302) consists of 2 arranged along the circumference of q concentric squares n A plurality of points, wherein q is a positive integer and there are four points at the corners of each of the concentric squares; and
-transmitting the symbol (303).
2. The transmitting device of claim 1, configured to:
converting the sequence of discrete constellation symbols (303) into a signal matching a transmission channel; and
the signal is transmitted to a receiving device (310).
3. The transmitting device (300) of claim 1 or 2, wherein:
said two dimensions 2 n The points of each concentric square of the symbol constellation (302) are evenly distributed along the circumference.
4. The transmitting device (300) of claim 1, wherein
Said two dimensions 2 n The symbol constellation (302) is also defined by the following features:
the sides of the concentric squares are parallel to the I-axis, Q-axis, and the center of the squares coincides with the origin of the I-Q plane,
the length of the sides of the ith square is Li, L 1 <L 2 <…<Lq，
The ith square contains 4.Ni points, ni is an integer and N 1 ≤N 2 ≤…≤Nq。
5. The transmitting device (300) of claim 4, wherein:
the two-dimensional 2 has been treated by minimizing the cost function n Parameter l= [ L ] of symbol constellation (302) 1 ,…,L q ]And n= [ N ] 1 ,…,Nq]Optimization was performed.
6. The transmitting device (300) of claim 5, wherein:
the cost function is expressed as:
f(L,N)＝RSNR+PAPR1D，
wherein L= [ L ] 1 ,L 2 ,...,L q ]，N＝[N 1 ,N 2 ,...,N q ]RSNR represents a desired signal-to-noise ratio at a target Bit Error Rate (BER), PAPR1D represents a peak-to-average power ratio in one dimension, and RSNR and PAPR1D are expressed in decibels.
7. The transmitting device (300) according to any of claims 4-6, wherein:
n is equal to 5 and,
q is equal to 3 and,
L 1 equal to 2, L 2 Equal to 6, L 3 Equal to 10
N 1 Equal to 1, N 2 Equal to 3, N 3 Equal to 4.
8. The transmitting device (300) according to any of claims 4-6, wherein:
n is equal to 7,
q is equal to 6 and,
L 1 equal to 2, L 2 Equal to 6, L 3 Equal to 10, L 4 Equal to 14, L 5 Equal to 18, L 6 Equal to 22
N 1 Equal to 1, N 2 Equal to 3, N 3 Equal to 5,N 4 Equal to 7, N 5 Equal to 7, N 6 Equal to 9.
9. The transmitting device (300) according to any of claims 1 to 2 or 4 to 6, for:
performing Gray mapping or quasi-Gray mapping to map the obtained message (301) to the two-dimensional 2 n On the symbol constellation (302).
10. A receiving device (310) adapted to use a two-dimensional symbol constellation, the receiving device (310) comprising a receiving module for:
receiving a sequence of noisy discrete constellation symbols (304);
using two dimensions 2 n A symbol constellation (302) demaps the sequence of noisy discrete constellation symbols (304) into output data (305), where n is an odd number not less than 3,
wherein the two dimensions 2 n The symbol constellation (302) consists of 2 arranged along the circumference of q concentric squares n A dot composition wherein q is a positive integer, anAnd four points at the corners of each of the concentric squares.
11. The receiving device (310) of claim 10, configured to:
-receiving a signal, in particular a signal from a transmitting device (300); and
the received signal is converted into a sequence of noisy discrete constellation symbols (304).
12. The receiving device (310) according to claim 10 or 11, for
Hard or soft demapping is performed based on gray mapping or quasi-gray mapping.
13. A method (900) of transmitting a message using a two-dimensional symbol constellation, the method comprising:
obtaining (901) a message to be sent;
mapping (902) the obtained message to two-dimensional 2 n On the symbol constellation, where n is an odd number not less than 3,
wherein the two dimensions 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A plurality of points, wherein q is a positive integer and there are four points at the corners of each of the concentric squares; and
the symbol is transmitted (903).
14. A method (1000) of receiving a message using a two-dimensional symbol constellation, the method comprising:
-receiving (1001) a noisy discrete constellation symbol sequence;
using two dimensions 2 n The symbol constellation demaps (1002) the noisy discrete constellation symbol sequence into output data, where n is an odd number not less than 3,
wherein the two dimensions 2 n The symbol constellation consists of 2 arranged along the perimeter of q concentric squares n A composition of points, wherein q is a positive integer and there are four points at the corners of each of the concentric squares.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP2019/053308 WO2020164683A1 (en) | 2019-02-11 | 2019-02-11 | A class of symbol constellations for data transmission |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113169949A CN113169949A (en) | 2021-07-23 |
| CN113169949B true CN113169949B (en) | 2023-06-02 |
Family
ID=65411873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201980082072.6A Active CN113169949B (en) | 2019-02-11 | 2019-02-11 | Symbol constellation diagram for data transmission |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US11658860B2 (en) |
| EP (1) | EP3912318B1 (en) |
| CN (1) | CN113169949B (en) |
| WO (1) | WO2020164683A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022135664A1 (en) * | 2020-12-21 | 2022-06-30 | Huawei Technologies Co., Ltd. | A unipolar pulse amplitude modulation for peak power constrained channels |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101867437A (en) * | 2009-04-20 | 2010-10-20 | 华为技术有限公司 | Base band mapping method, mapper and transmitter of communication system |
| CN104471861A (en) * | 2012-07-27 | 2015-03-25 | 松下电器产业株式会社 | Transmission method, reception method, transmitter, and receiver |
| CN107040492A (en) * | 2017-06-07 | 2017-08-11 | 重庆邮电大学 | A kind of novel coded modulation scheme of the LDPC code based on 8 QAM signals |
| LU93085B1 (en) * | 2016-05-24 | 2017-11-29 | Univ Luxembourg | Data transmission method and device |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7535975B1 (en) * | 2003-11-07 | 2009-05-19 | Wionics Technologies, Inc. | QAM mapping and bit labeling or bit-interleaved coded modulation |
| AU2007214342A1 (en) * | 2006-09-20 | 2008-04-03 | Nec Australia Pty Ltd | Demodulation method |
| US9571326B2 (en) * | 2009-03-05 | 2017-02-14 | SeeScan, Inc. | Method and apparatus for high-speed data transfer employing self-synchronizing quadrature amplitude modulation |
| US8848830B2 (en) * | 2011-11-17 | 2014-09-30 | Intel Mobile Communications GmbH | Method for providing a modulation scheme |
-
2019
- 2019-02-11 CN CN201980082072.6A patent/CN113169949B/en active Active
- 2019-02-11 EP EP19705156.8A patent/EP3912318B1/en active Active
- 2019-02-11 WO PCT/EP2019/053308 patent/WO2020164683A1/en unknown
-
2021
- 2021-08-10 US US17/398,418 patent/US11658860B2/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101867437A (en) * | 2009-04-20 | 2010-10-20 | 华为技术有限公司 | Base band mapping method, mapper and transmitter of communication system |
| CN104471861A (en) * | 2012-07-27 | 2015-03-25 | 松下电器产业株式会社 | Transmission method, reception method, transmitter, and receiver |
| LU93085B1 (en) * | 2016-05-24 | 2017-11-29 | Univ Luxembourg | Data transmission method and device |
| CN107040492A (en) * | 2017-06-07 | 2017-08-11 | 重庆邮电大学 | A kind of novel coded modulation scheme of the LDPC code based on 8 QAM signals |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113169949A (en) | 2021-07-23 |
| EP3912318B1 (en) | 2024-04-03 |
| WO2020164683A1 (en) | 2020-08-20 |
| EP3912318A1 (en) | 2021-11-24 |
| US20210367828A1 (en) | 2021-11-25 |
| US11658860B2 (en) | 2023-05-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101518013B (en) | Method and system to reduce papr in single carrier and scbt communications systems | |
| US9306791B2 (en) | Method for designing an amplitude and phase shift keying constellation | |
| US9246525B2 (en) | Device and method for predistortion | |
| KR100452789B1 (en) | Pilot signal transmission technique and digital communication system using same | |
| CN110971559B (en) | Modulation and demodulation method for reducing peak-to-average power ratio of OFDM-PON signal | |
| CN113169949B (en) | Symbol constellation diagram for data transmission | |
| US8971450B2 (en) | Transmission device, reception device, transmission method and reception method for wireless communication system | |
| US9231705B1 (en) | Communication system with QAM modulation | |
| US9473244B2 (en) | Flexible 400G and 1 Tb/s transmission over transoceanic distance | |
| US10567209B1 (en) | Geometrically shaping QAM modulation | |
| WO2021233536A1 (en) | A peak power efficient modulation format for un-amplified optical fiber links | |
| Caldwell et al. | M-ary Hyper phase-shift keying over non-linear satellite channels | |
| EP3122013B1 (en) | Coded modulation and demodulation method, apparatus and system | |
| WO2014122285A1 (en) | Transmitter for performing an 8-qam or a 7-qam modulation and correspondent receiver | |
| Song et al. | Alamouti code with quadrature partial response signaling | |
| KR20050032952A (en) | Method and system for transmitting signal in spatial multiplexing system by using multidimensional rotated modulation | |
| Lee et al. | New bits-to-symbol mapping for 32 APSK over nonlinear satellite channels | |
| DJEMAMAR et al. | Performance Analysis of QPSK, 4QAM, 16QAM and 64QAM with Binary and Gray Constellation Codes over AWGN Channel | |
| JP2004274797A (en) | Transmission method and transmission apparatus | |
| JP2000224248A (en) | Digital radio communication system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |